Thoracic Endovascular Aortic Repair on Zone 2 Landing for Uncomplicated Type B Aortic Dissection with Measurement of Intra-False Lumen Pressure.

OBJECTIVE: This study aimed to evaluate the mid-term results of zone 2 thoracic endovascular aortic repair (TEVAR) for uncomplicated type B aortic dissection (TBAD) by measuring the intra-false lumen pressure (IFLP) during TEVAR.

METHODS: Fifteen patients (9 men; mean age, 57 years) who underwent zone 2 TEVAR for uncomplicated TBAD were reviewed. Delta systolic pressure (defined as the difference between systemic pressure and IFLP) was measured before and after primary entry closure, and aortic remodeling and thrombo-occlusion of the false lumen (FL) were evaluated 12 months after TEVAR at five different levels of the aorta.

RESULTS: Median duration from onset to TEVAR was 34 days. The left subclavian artery was preserved in 13 patients (87%) by using stent graft fenestration. Although one patient (6%) had a transient cerebral infarction, there were no severe TEVAR-related complications. Entry closure significantly reduced delta systolic pressure (mmHg) compared to preoperative pressure at all levels (distal arch: -22.2±10.8 vs -5.2±9.6; Th8: -20.1±12.4 vs -6.9±7.2; Th10: -14.3±14.6 vs -4.7±7.5; Th12: -14.4±14.5 vs -4.9±7.8; L2: -14.5±14.2 vs -3.4±6.9). The percentages of aortic remodeling with expansion of the true lumen (distal arch: 82%; Th8: 80%; Th10: 54%; Th12: 45%; L2: 50%) and complete false lumen thrombosis (distal arch: 100%; Th8: 100%; Th10: 67%; Th12: 11%; L2: 0%) were approximately consistent with the change in delta systolic pressure. During a follow-up of 41 months, distal stent-induced new entry occurred in two patients (13%) requiring secondary intervention; however, there were no cases of FL enlargement or aorta-related mortality.

CONCLUSION: Zone 2 TEVAR for uncomplicated TBAD may prevent TEVAR-related complications. Measuring IFLP could be a new predictive marker for assessing the extent of aortic remodeling.